Microphone device



Dec. 20, JUCKER MICROPHONE DEVICE 2 Sheets-Sheet 1 Filed July 2, 1963 Dec. 20, 1966 E. JUCKER MICROPHONE DEVICE 2 Sheets-Sheet 2 Filed July 2, 1963 INVENTOR. I E/Q/CH JUC/(ER in which it operates when carried by its user.

United States Patent 3,292,416 MICROPHONE DEVICE Erich Jucker, La Chaux-de-Fonds, Switzerland, assignor to Le Porte-Echappement Universal S.A., La Chaux-de- Fonds, Switzerland Filed July 2, 1963, Ser. No. 292,421 4 Claims. (Cl. 73-6) The present invention relates to microphones for use in chrono-comparators; more particularly, this invention relates to apparatus for automatically moving the receiving heads of such microphones into different pre-selected positions.

A chrono-comparator is a device for timing and regulating watches and other similar timing 'devices. One well-known type of chrono-comparator uses a microphone to detect the ticking sounds produced by the watch and then converts thme sounds into linear marks which are recorded on a record sheet. From these marks characteristics of the watchs operation can be determined. For example, it can be determined whether the watch is running too slow, too fast, or on time.

The present invention relates to microphones used in chrono-comparators of the type described above. Typically, these microphones include a clamping device by means of which the watch is attached to the microphone head. A membrane and a piezo-electric element are provided to convert the ticking sounds of the watch into corresponding electrical signals. These electrical signals are transmitted to associated electrical equipment which converts them into the recorded marks.

It is desirable to record the ticking sounds of a watch with the watch oriented in a number of different positions so as to test the time-piece in positions similar to those Microphone devices for chrono-compa-rators have been produced in which the microphone head is manually movable to a multiple of different positions. Operation of these devices, however, is costly since the devices require considerable surveillance and labor to use.

Chrono-comparator microphone devices in which the microphone head is moved automatically to several different positions have been proposed. However, these devices have serious disadvantages. Some of them rotate the microphone head about a single axis by means of an electric motor. This arrangement is unsatisfactory because rotation about a single axis does not provide enough variability in the positioning of the microphone head. In

other proposed arrangements, rotation about two orthogonal axes is obtained by the use of cams or gearing to couple the microphone head to a single motor. A disadvantage with these arrangements is that the speed of rotation about one axis is a function of the speed of rotation about the other axis. This is not desirable because the speed around each separate axis should be chosen in such a. way as to optimize the response of the microphone without adversely affecting the action of the watch mechanism. Thus, for optimum operation of the chrono-comparator, the speeds about the separate axes should be independent from one another.

in the precise measurements and adjustments made upon precision time-pieces, it is important that vibration and other disturbances be kept at a minimum. Previous automatic microphone positioning arrangements are unsatisfactory for the reason that their motors, cams and gears produce considerable amounts of vibration. This vibration, besides being destructive'to the structure of the moved from one measurement position to another. This adds time, cost, and inaccuracy to the checking process.

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Accordingly, an object of this invention is to provide a microphone device for use in chrono-comparators which device moves the microphone head automatically to a plurality of desired positions.

Another object of this invention is to provide such a microphone device which rotates the microphone head simultaneously about two orthogonal axes, the speed of rotation about one of said axes being independent from the speed of rotation about the other of said axes.

A further object of this invention is to provide such a microphone device whose motion is substantially free of vibration and is adapted to allow the mechanism of a timepiece attached to the microphone head to 'be adjusted while the microphone head is moving from one measurement position to another.

Another object of this invention is to provide such a microphone device which is accurate, reliable, free from malfunction and relatively inexpensive to manufacture.

The drawings and descriptions that follow describe the invention and indicate some of the ways in which it can be used so as to meet the above-stated objects. In addition, some of the advantages provided by the invention will he pointed out.

In the drawings:

FIGURE 1 is an elevation view, partially cut-away, of a microphone device embodying the present invention;

FIGURE 2 is a section view taken along line II--II of FIGURE 1 in the direction of the arrows; and

FIGURE 3 is a side elevation view of the microphone device shown in FIGURE 1, with one side of the stationary casing removed.

The automatic mincrophone device shown in the drawings includes a stationary housing 1 having six walls attached to four support rods 2. Side walls 3 of housing 1 are fitted into longitudinal grooves in rods 2 and the end Walls are attached to the ends of the rods by means of screws. The automatic microphone device also ineludes movable housing 4 whose six walls include four side-walls 6 and a pair of end walls which are similarly secured to four posts 5." Stationary housing 1 is secured to a pair of support members 7 which form a base upon which the microphone device sits.

A synchronous motor 8 is mounted in housing 1. It is adapted to rotate alternately clockwise and counter clockwise and drives a shaft 12 through a friction cou pling mechanism which includes a friction wheel 10 attached to the output shaft 9 of motor 8, and a disk segment 11 which is engaged by friction wheel 10. The surface of wheel 10 has a coating of flexible material to provide a firm grip between wheel 10 and disk segment 11 and to ensure that no vibration is produced by the coupling. Shaft 12 is mounted in a bearing 13 which is integral with end wall 14 of stationary housing 1. A hub 15 which is integral with wall 16 of movable housing 4 is secured to the external end of shaft 12. As is described in greater detail below, movable housing 4 is rotated alternately clockwise and counterclockwise about the longitudinal axis of shaft 12 by synchronous motor 8.

A second synchronous motor 17 is mounted in movable housing 4. Synchronous motor 17 is adapted to drive its output shaft 18 in only one direction. Attached to one end of shaft 18 is another friction coupling mechanism which includes a friction wheel 19 which engages the inner portion of a drum 20. Friction wheel 19 has a coating like that of friction wheel 10. Drum 20 is secured to a hollow shaft 21 which is rotatably mounted in a bearing 22. A microphone head 23 is attached to the end of shaft 21.

Microphone head 23 may be of any type desired including the type described above that includes a mem- I one of these indentations.

brane and a piezoelectric element. It also may have a clamping device of the type described above for holding a time-piece to be tested. The electrical lead wire 24 for this microphone is aligned longitudinally in the hollow central portion of shaft 21. Its lower end touches a contact arm 25 which is affixed to an electrical terminal 26.

Synchronous motor 17 is mounted on a movable plate 27 which is pivoted on a spindle 28. Spindle 28 is secured to fixed plate 29 which is attached to the upper end wall 30 of housing 4 by means of three support rods 31. Mechanical pressure between friction wheel 19 and drum 20 is maintained by a calibrated spring 32 fastened at one of its ends to movable plate 27 and at its other end to fixed plate 29.

The microphone device shown in the drawings is adapted to be used, preferably, with a programming device (not shown) which automatically energizes one or both of the electric motors in a desired sequence to move the microphone head 23 successively to each of several measurement positions. When a measurement position is reached, electrical contact means (to be described below) de-energizes the motors and the recording apparatus is started. When the recording has been completed, the programming device automatically re-energizes one or both of the motors which move the microphone head to a new measurement position. If desired, manual instead of antomatic switching means can be provided to start each recording cycle.

The mechanism for de-energizing motor 17 to stop microphone head 23 at selected measurement positions includes a set of spring-blade electrical contacts 33 having a projection which mates with several serially-arranged indentations 34 in the upper surface of drum 20. Contacts 33 are closed each time the projection mates with Two other sets of electrical contacts 35 and 36 have projections which similarly mate with indentations in the peripheral surface of drum 20. Each of these contacts opens when its projection mates with an indentation. Contacts 33, 35 and 36 are electrically connected to the programming device and motor 17 and co-operate with the programming device in automatically stopping and starting the motor to provide the desired measurement stops.

Referring now to FIGURE 3 as well as FIGURE 1, the stationary synchronous motor 8 is mounted on a movable plate 37 which is pivoted on a spindle 38. Spindle 38 is secured to a fixed plate 39 which is attached to the end wall of the housing 1 by means of three support rods 40. Mechanical pressure between friction wheel and disk segment 11 is maintained by a calibrated spring 41 fastened between stationary plate 39 and movable plate 37.

The angular distance that shaft 12 rotates is controlled by a cam 43 which is secured to output shaft 9 of motor 8 and engages a set of electrical contacts 42 which is adapted to de-energize motor 8 when the angular rotation of cam 43 has reached 90 degrees. A set of contacts 44 is engaged by a projection 45 on disk segment 11 when the segment reaches the end of its counterclockwise movement. Contacts 44 are electrically connected to the programming device and motor 8 to reverse the motors direction of rotation.

Thus, in the embodiment shown in the drawings, movable housing 4 and microphone head 23 are rotated alternately clockwise and counterclockwise between measurement positions angularly located at an angle of 90 degrees from one another.

Synchronous motors 8 and 17 are particularly noiseless and vibration-free. Moreover, as mentioned above, the coatings for wheels 10 and 19 prevent the drive couplings from producing vibrations or other disturbances. Thus, the device of the present invention provides extremely smooth rotation of the microphone head around two orthogonal axes. This represents a substantial improvement over previous cam or gear couplings in which the clash of the mating metal parts produces serious disturb-. ances which interfere with adjustment of the delicate Watch mechanisms. This improvement makes it possible to make fine adjustments in the watch mechanism while the watch is being moved from one measurement position to another, thus decreasing the time and cost of the meas- Y urement process.

The above description of the invention is intended to be illustrative and not in limitation thereof. Various changes or modifications in the embodiment described may occur to those skilled in the art and these may be made without departing from the spirit or scope of the invention as set forth in the claims.

I claim:

1. Apparatus for automatically moving the sound-re ceiving heads of microphones used in chrono-comparators into a plurality of positions which are pre-selected to permit the measurement of the operational characteristics of a time-piece when it is aligned in a number of different orientations, said apparatus comprising, in combination, a

first housing adapted to form a base support for said apparatus, a first electric motor mounted in said housing, a drive shaft for said first motor, a friction wheel mounted on said first drive shaft, said friction wheel having a cush-;

ioning, friction-inducing exterior surface, a drive segment engaged with said friction wheel and secured to a first out-1 put shaft, said first motor being adapted to drive said out-; put shaft either clockwise or counterclockwise, means including electrical contacts for reversing the direction of rotation of said first motor when it has rotated to a preselected position, a second housing secured to said first output shaft, said second housing containing a second electric motor having a drive shaft, a second friction wheel attached to said second drive shaft, said second wheel having a cushioning, friction-inducing exterior surface, a

drum driven by said second friction wheel, a second out parator microphones into a plurality of positions which.

are pre-selected to permit the measurement of the operational characteristics of a time piece when it is aligned in i a number of different orientations, said apparatus comprising, in combination, a microphone support member, a first drive motor coupled to said support member to rotate said support member about a first axis, a second drive motor coupled to said support member to rotate said support member about a second axis, said first and second axes being angularly spaced from one another, means for sequentially energizing and de-energizing said motors automatically in a programmed sequence, said last-named. means including electrical switching means and means for 3. Apparatus as in claim 2 in which said automatic reversing means includes switches, each located angularly with respect to the other, and cam means drivably coupled to said first motor to actuate said switches to provide automatic reversal of rotation of said first motor in both the clockwise and counter-clockwise directions.

4. Apparatus as in claim 2 in which said first axis is substantially horizontal and said second axis is substantially perpendicular to said first axis.

(References on following page) References Cited by the Examiner UNITED STATES PATENTS Marti et a1. 736

6 FOREIGN PATENTS 295,742 3/1954 Switzerland.

LOUIS R. PRINCE, Primary Examiner.

STEVEN H. BAZERMAN, Assistant Examiner. 

1. APPARATUS FOR AUTOMATICALLY MOVING THE SOUND-RECEIVING HEADS OF MICROPHONES USED IN CHRONO-COMPARATORS INTO A PLURALITY OF POSITIONS WHICH ARE PRE-SELECTED TO PERMIT THE MEASUREMENT OF THE OPERATIONAL CHARACTERISTICS OF A TIME-PIECE WHEN IT IS ALIGNED IN A NUMBER OF DIFFERENT ORIENTATIONS, SAID APPARATUS COMPRISING, IN COMBINATION, A FIRST HOUSING ADAPTED TO FORM A BASE SUPPORT FOR SAID APPARATUS, A FIRST ELECTRIC MOTOR MOUNTED IN SAID HOUSING, A DRIVE SHAFT FOR SAID FIRST MOTOR, A FRICTION WHEEL MOUNTED ON SAID FIRST DRIVE SHAFT, SAID FRICTION WHEEL HAVING A CUSHIONING, FRICTION-INDUCING EXTERIOR SURFACE, A DRIVE SEGMENT ENGAGED WITH SAID FRICTION WHEEL AND SECURED TO A FIRST OUTPUT SHAFT, SAID FIRST MOTOR BEING ADAPTED TO DRIVE SAID OUTPUT SHAFT EITHER CLOCKWISE OR COUNTERCLOCKWISE, MEANS INCLUDING ELECTRICAL CONTACTS FOR REVERSING THE DIRECTION OF ROTATION OF SAID FIRST MOTOR WHEN IT HAS ROTATED TO A PRESELECTED POSITION, A SECOND HOUSING SECURED TO SAID FIRST OUTPUT SHAFT, SAID SECOND HOUSING CONTAINING A SECOND ELECTRIC MOTOR HAVING A DRIVE SHAFT, A SECOND FRICTION WHEEL ATTACHED TO SAID SECOND DRIVE SHAFT, SAID SECOND WHEEL HAVING A CUSHIONING, FRICTION-INDUCING EXTERIOR SURFACE, A DRUM DRIVEN BY SAID SECOND FRICTION WHEEL, A SECOND OUT- 